Calculate edit distances and edit scripts between vectors. https://github.com/thsutton/edit-distance-vector

Version on this page:
LTS Haskell 13.22:
Stackage Nightly 2019-05-22:
Latest on Hackage:

See all snapshots edit-distance-vector appears in

BSD-3-Clause licensed by Thomas Sutton
Maintained by me@thomas-sutton.id.au

Module documentation for

Edit Distance: Vector

Build Status

This is a small library for calculating the edit distance and edit script between two vectors. It is generic enough that you should be able to use it with vectors containing values of any type you like, with changes described by any type you like, and with costs represented by any type you like (with a few restrictions).


The edit-distance-vector package is a normal Haskell library and can be installed using the Cabal package management tool.

cabal update
cabal install edit-distance-vector

edit-distance-vector is automatically tested on GHC versions 7.4.2, 7.6.3, 7.8.3, 7.10.1, 8.0.2 using the Travis CI service.


The interface to edit-distance-vector is very small; just import Data.Vector.Distance, create a Params value with the correct operations to deal with your types, and pass this to leastChanges along with your Vectors.

import           Data.Monoid

import qualified Data.Vector          as V
import           Data.Vector.Distance

-- | Editing vectors of 'Char' values, with '(String, Int, Char)' describing
--   changes, and the additive monoid of 'Int' describing costs.
str :: Params Char (String, Int, Char) (Sum Int)
str = Params
    { equivalent = (==)
    , delete     = \i c    -> ("delete", i, c)
    , insert     = \i c    -> ("insert", i, c)
    , substitute = \i c c' -> ("replace", i, c')
    , cost = const (Sum 1)
    , positionOffset = \ (op, _, _) -> if op == "delete" then 0 else 1

main :: IO ()
main = do
    print $ leastChanges str (V.fromList "I am thomas")
                             (V.fromList "My name is Thomas")

(See test/sample.hs for a version of this code that is compiled by the automated test suite.)



* Relax version bounds to support GHC 8.0


* Relax version bounds to support GHC 7.6.3 and 7.4.2


* Relax version bounds to support GHC 7.6.3 and 7.4.2


* Relax version bounds to support GHC 7.10.1.

edit-distance-vector 1.0

* Initial release extracted from aeson-diff package and rewritten to use
Depends on 2 packages:
Used by 2 packages:
comments powered byDisqus